While watching a prior-art sound movie, a viewer often experiences a vicarious sense of involvement. Such passive involvment can be changed to active participation if the movie branches, that is, if each scene is followed by one of several alternative scenes, each having different sound or different picture or both.
An example of a prior-art branching movie is shown in U.S. Pat. No. 3,960,380 titled "Light Ray Gun and Target Changing Projectors". This system uses a pair of film projectors which present two alternatives (hit or miss) at each branch point. An example of a prior-art device for interactive voice dialog is shown in U.S. Pat. No. 4,016,540. This device does not present a motion picture. An example of a prior-art video editing system is shown in U.S. Pat. No. 3,721,757. This system displays a sequence of video excerpts specified by a control program of stored videodisc addresses which comprise a sequential (not branching) movie. To change this sequence the editor alters the program. In the present invention the viewer does not alter the program.
Push-button controlled branching movies are used for computer-assisted education systems which display a lesson segment and multiple choice questions to each student. Such a system is described by R. K. Wood in Educational and Industrial TV, May 1979, pp 31-42, in an article titled "The Utah State University Videodisc Innovations Project". Depending on the student's answer, the movie branches to a segment which contains reinforcement for correct answers, or to a segment which provides remedial lessons for wrong answers.